Jar rings, or screw bands, should definitely be removed
before storing jars because some spoilage organisms
produce gas causing the lid to swell and come unsealed.
If jar rings are removed before storage, it is easy to
see if lids have come unsealed. Additionally, if enough
internal pressure is present and rings are left on, jars
may burst. Remember not to remove rings or disturb jars
in any way for 12 to 24 hours after heat processing. The
vacuum inside jars gets stronger over the 12 hours after
heat processing. Leaving the ring on during this period
helps the vacuum form.